Advantages of the Rototherm®
- Fully–wetted process wall at all evaporation- and feed rates, hence less fouling
- Thin film unaffected by gravity, thus a high turn-down ratio
- Higher heat flux due to more uniform film
- Considerably less solvent required for cleaning
- Readily accessible external bearings and double mechanical seals
- No internal bottom bearing in contact with the process stream
- Easy installation and maintenance
The Rototherm® has several executions.
- Rototherm-E: Designed as an evaporator or finisher with a liquid product stream as end-product.
- Rototherm-P: Designed to go one step further as it produces a dry output directly from a liquid feed.
- Rototherm-D: Designed to post-dry solid streams of material.
- Protherm-50: Designed as a versatile test unit
Rototherm® – Design features
Rototherm® units may be designed for co-current or counter-current liquid/vapour flow.
Rototherm® – Principle of operation
The turbulent thin or wiped film creates high heat transfer efficiency, thus minimizing the area required for evaporation. The film is continuously renewed by the incoming feed as the progressively more concentrated material moves towards the bottoms discharge nozzle. Product residence time in the Rototherm is generally measured in seconds, minimizing degradation of heat-sensitive materials.
Rototherm – Principle of Operation
Rototherm allows for up to 99% evaporation in a single pass. As a consequence it can often concentrate dilute solutions to powder directly. Markedly dry spots do not exist, as the process wall, unaffected by gravity, remains fully wetted at all evaporation rates.
When used as a continuous reactor, the Rototherm’s multiple feed points and temperature zones, its controlled residence time, and simultaneous evaporation of reaction by-products provide total flexibility for complex reactions. Rototherm’s short residence times allow reactions at higher temperatures than conventional reactors. As such increasing the rate of reaction without compromising product quality and yield.
Artisan designs each Rototherm for optimum performance for its specific application. Rototherms can range in size from 1 dm2 to 23 m2 of heated surface. A single unit can evaporate up to 2,000 kilograms of solvent per hour. Rototherm jackets can be designed for hot water, steam or hot oil heating. Construction materials include stainless steel (300 series and Duplex), carbon steel, nickel, Inconel®, Monel®, Hastelloy®, and titanium.